Worsbrough Bridge lost in midweek, meaning fellow Barnsley club Dearne and District can win the NCEL Division One title on Friday.
If Dearne win at Club Thorne on Friday they will secure the only automatic promotion place.
Bridge lost 3-2 at Route One Rovers, one of the teams just below them, on Wednesday. That ended a six-game winning run.
The hosts took the lead then Keelan Grist levelled. Bridge went 3-1 down before Benjamin Pike replied.
They are fourth, eight points clear in the play-off places.
They need another 14 points to guarantee a place in the play-offs for the first time in their history. Their current tally of 73 points is the most they have ever collected in an NCEL season.
